In orthopedic surgery and in particular implant surgery, various instruments for removing or machining bone tissue are well known, such as milling tools, surgical fraises, reamers, drills, rasps, and others. Such instruments may present in various different forms, each adapted to the specific cavity required within the bone tissue. For example, instruments may be generally spherical or hemispherical, cylindrical, tapered, or more complicated combinations of shapes.
Any of those tools may be designed for use as a hand tool or a machine tool, and may thus also be provided with adaptors or connection elements for grips, driving elements or further options.
In order to minimize any risk of infection during surgery, instruments and tools are increasingly provided as disposable tools for single use. Such instruments need to fulfil certain characteristics:                providing optimal precision in order to provide a stable bone cavity for primary stability of an implant, and to obtain required surface quality;        obtaining a bone cavity essentially free of bone and cartilage chippings and cuttings, so that any need for rinsing and suctioning of the cavity during surgery is minimized;        reduced cutting resistance for reamers and fraises, and reduced intramedullary pressure;        reducing manufacturing costs;        easy collection of bone material, e.g. for grafting;        simple and secure disposal of single-use instruments.        
An example of a disposable surgical reamer is given by US patent application No. 2011/0202060A1, where the reamer is assembled from multiple parts. A hemispherical surface with cutting elements is combined with a base element and internal structural supports. Further examples are given in U.S. Pat. No. 6,120,508, disclosing a disposable bone rasp.
While there are surgical instruments which fulfil some of these criteria, there is a need for an improved tool and manufacturing method which optimizes all required features.